Underreamer.



C. S. WRIGHT.

UNDERREAMER.

APPLICATION FILED ocr.24. 1916.

'llullll Patented Oct. 9,1917.

2 SHEETS-SHEET l INVENTOH 2 C. I.W- 60 C. S. WRIGHT.

UNDERREAMER.

APPLICATION man ocr. 24, ms. 7 1,242,508. Patented 0011.9,1917.

' 2 EEEEE SSHET 2-- CLYDE s. WRIGHT, or ToLEDqoHIo, ASSIGNORTO THE NATIONAL SUPPLY COMPANY,

' or'roLEno, 01110, A CORPORATION or OHIO. Y

' UNDERREAVMER.

To all whom it may concern: 7

Be it known that I, CLYDE WRIGHT, a citizen of the United States','residing at Toledo, in the county of Lucas and State of Ohio, have invented new and useful Improvements in Underreamers, of following is a specification. e 1

My invention relates. to underreamers and its object is to provide an ,underr'eamer which shall have avery simple construction whereby the cost may be kept'lo'w and the parts are'not liable to get out of order. 7

Referring to the accompanying drawings,

Figure l is a side elevation of'anunder-i reamer constructed in accordance with the prmciples of my invention, aport onbemg broken away; Fig. 2, a vertical section of I the underreamer with the bits expanded," the upper part of theunderreamer and the'well casing being broken away Fig. 3 a section similar to Fig. 2'but showing the bitscollapsed; and Fig. 4:, a bottom plan view of Fig. 2. Figsa5 to 9 are sections of Fig. 2 on the lines V V to IXIX, respectively;

On the drawings, 1 represents the elon gated cylindrical body of my un'derreamer having the threaded upper end 2 forconnecting the body to a line of drill-rods not shown. The body l has the axial or central opening 3 preferably closed at its-upper end and 'communicatingat'the lower end with the bit-receiving chamber which com prises three portions, namely, the upper preferably annular portion 4 having a larger diameter than the diameter of the opening 3 above the same, the large lower preferably cylindrical'portion 5 extending tothe bottom of the body 1, and the intermediate portion 6 between the portions 1 and 5, its diameter being smaller than that of either of the other portions. v

7 is a collar seated in the lower end of the opening 3 just above the portion 4 o'f'the bit-receiving chamber, and issecured therein by means of the pin 8 which extends through the body 1 and a portion of the annular groove 10 in the collar.

11' is a rod reciprocable in'theopening 3, the collar 7 v and the .said chamber, and has its upper end screwed into the slotted nut 12 reciprocable in the upper end of "the opening 3. An expansion spring 18 sur- Specification of Letters l atente which the rounds the rod 11 and bears: at one end against the under sideof the slotted nut 12 and at theother end "against the upper .side of the collar 7. v

V The-portionof the body 1 =a short distance'above the collar,7-,"'is provided with Patented Oct. 9, 1917, 5 Application filed. October aewis serial'no.127,34 :1

diametrically opposite slots 14k extending from the periphery ofithe body entirely through tothe opening 3. The slots 14: are widened near their upper ends as shown at 15. .Iprovide eachslot'le with anelbow lever 16, one member 17 of each lever'extending'transversely of the body 1' to the cente'rof the opening 3 and to the middle er the slot 18 in the upper end of the slotted nut 12. The other members of theelbow upper faces substantially flush with the pe riPher-V' ofthe y The upper 'endsof the recesses 20 are beveled outwardlyandupwardly tocorrespond'with bevels on the upper ends otthe head's'19 to facilitate the movement of th heads into' and from the recesses. The transverse members of the el'- bow levers are somewhat thickened 'to' pro levers -16 lie lengthwise in the slots 1a and vide heads or bearings 21. These heads or bearings are adapted'to'be passed through the widened "portions of the slots- 14 and into the opening 3. These heads or bear ings, being somewhat larger than the width of the slots-14, prevent the lever 16"from moving outwardly through'the slots 14L when :3

the heads of bearings are above orjb'elow the said widened portions 15-015 the slots 14. The opposing ends of the transverse members of the levers 16 arefbeveled upwardly and outwardly so that when the levers have their heads 19 in the recesses 20,

there is a wedge-shapedopening'between the said opposing ends of the levers andiso that the levers may swing outwardly from the position shown on Fig. 3' to that shown onriga... r I provide a pair of bits 22 having-the same construction.- Each-bit has" at itsup per end-an outwardly extendin'g fiange 23 which extends into the recesses" constituting the upper portion 4 of the bit-receiving chamber. Each bit has also the portion 21 which is adapted to fit against the 'wall of the bottom portion 5 of the said chamber when the bits are in their expanded, or most widely separated, position. The portions 25 of the bits lie between the portions 23 and 2 1 and rest against the walls of the intermediate portion 6 of the said chamber when the bits are most widely expanded. The bitshave below the portions 24: the portions 26 provided at their upper ends with the shoulders 27 lying immediately below the lower end of the body 1. The outer surfaces of the portions 26 of the bits extend slightly beyond the periphery of the body 1 when the bits are most widely expanded, the outer surfaces of the portions 26 being inclined downwardly and outwardly to the cutting edges 28. When the bits are in their expended position, shoulders 27 abut against the lower end of the body 1, and the upper ends of the portions 2 1 of the bits abut against the upper wall of the portion 5 of the bit-receiving chamber. When the bits are in their collapsed position, as shown on Fig. 3 they are supported by the flanges 23 which rest on the lower wall of the upper portion 4 of the said chamber. I o

It will be noticed from Fig. 2 that, when the bits are in their expanded position, their opposing edges are separated at somedistance from each other and it will be noticed from Fig. 3 that when the bits are in their collapsed position, the lower portions of the bits lie close together and that the outer faces of the bits lie within the periphery of the body 1 and substantially parallel therewith. It thus appears that the flanges 23 act as suspending means for the bits.

The rod ll extends down between the bits 26 which lie so closeto the said rod as to prevent the upper ends of the bits from moving inwardly toward each other, thereby preventing their dropping down through the body of the underreamer. It will be seen from Fig. 3 that even when the bits are collapsed, the upper ends thereof are separated by a space, at least, equal to the distance the flanges 23 extend outwardly be yond the portions of the bits, so that when the rod 11 is withdrawn from the underreamer the upper end of one bit may be moved toward the other bit and then withdrawn downwardly through the bit-receiving chamber. when one bit has been removed the other bit can be removed in. a similar manner.

The lower end of the rod 11 is provided with a bit-separating head 30 which, when the spring 13 is allowed to expand, is drawn upbetween the bits as shown in Fig. 2. This head has its sides beveled to correspond with inclined cooperating portions of the bits. The head 30 has at its upper end wedgeshaped lugs 31 which are adapted to enter between the meeting faces of the collapsed bits and move them apart at their lower ends. The opposing walls of the bits are provided with transverse shoulders 32 and the head 30 is provided with correspondingly shaped shoulders which bear against the shoulders 32 when the head 30 is in its uppermost position. The sides of the head 30 both above and below its said shoulders are tapered upwardly toward each other so that when the head 30 moves upwardly it will force the bits outwardly to their fully expanded position. where they are securely held by the sides of the head 30. The bottom of the head 30 is provided with an elongated recess 33 to receive the lugs on the lower end of the rod 11, thepin 37 passing through the lower end of the head 30 and the rod 11, whereby the said head is securely held on the rod.

I provide diametrically opposite lugs 35 which extend through the body 1 andinto slots 36 in the portions 24 of the bits in order to prevent the bits from accidental rotation in the body, since if they were free to rotate it might cause the rod 11 to be screwed out of the slotted nut 12. p

The parts being as shown in Fig. 3, in which the bits are shown collapsed and the heads 19 of the levers 16 are shown in the recesses 20, the underreamer is pushed down into. the well-casing or drill-pipe 36. The size of the underreamer and of the casing or drill-pipe 36 should be such as to prevent 100 the levers 16 from moving laterally out 'of the slots 14 sufliciently to allow the heads 19 to escape from the recesses '20, for ifthe said heads 19 should escape out of the recesses 20, the spring 13 would draw the bit- 105 separating head 30 upwardly and cause the cutting edges of the bits to be expanded against the casing or tube 36 and interfere with the downward movement of the underreamer. r i

hen the underreamer has been pushed below the lower end of the casing or pipe 36, the spring 13 at once causes the levers 16 to be swung outwardly, thereby freeing. the heads 19 from the recesses 20. The slot- 115 ted nut 12, the levers 16, the rod 11 and the bit-separating head 30 are all. moved upwardly by the spring 13 and the bits 22 are moved to their expanded position as shown in Fig. 2. I

l/Vhen the underreamer is drawn upwardly from its position shown in Fig. 2, the heads 19 engage with the lower end of the casing or tubing 36 and prevent the upward movement of the levers 16, the slotted 125 nut 12, the rod 11, and the bit-separating head 30, while the body 1, the collar 7, and the bits 22 continue their upwardmovement.

As soon as the recesses 20 come opposite the said heads 19, the latter are forced inwardly 13 up throu'gh'the-c asing. If only oneglever' be used it might be possible for the under reamer to pass partially up through a dis torted or elliptical shoe without the lever being operated so as to lower the head 80 and allow the bits to collapse. In such a case the underreamer might by reason of the expanded condition of the bits become so wedged in the shoe that it would be very difficult, if not impossible, to get the underreamer out of the Well. Each lever 16 can work independently so that if one breaks or fails to work the remaining one might still operate to release the bits.

I claim 1. In an underreamer, an elongated body having a central bore communicating at its lower end with a bit-receiving chamber, having lateral recesses at its upper end and a relatively large portion at its lower end,

bits having at their upper ends lateral flanges in the recesses and at their lower ends cutting edges, the bits being suspended .on the said flanges, and adapted to swing in the larger portion of the chamber, a reciprocable rod situated in the bore and between the bits, a bit-separating head on the lower end of the rod, and means for holding the rod in one position to separate the bits and in another position to allow the bits to collapse.

body, bits connected to the lower portion thereof so as to have free oscillating motion, a reciprocable rod arranged between the bits and in the bore in the body, a bit separating head on the lower end of the rod arranged to separate the bits when the rod is in its upper position, a slotted device on the rod, an elbow lever having one arm extending through the body and into the slot in the said device and having the other arm extending toward the bottom of the body, yielding means for moving the rod upwardly andholding the same in its upper position, and means on the lever, adapted for engagement with the interior of a pipe, for retaining the rod in its lower position.

3. In an underreamer, a centrally bored body, bits connected to the lower portion thereof so as to have free oscillating motion, a reciprocable rod arranged between the bits and in the bore in the body, a bit separating head on the lower end of the rodarranged to separate the bits when the rod is in its upper position, a slotted device onthe upper 52. In an underreamer, a centrally bored end ofithe rod, elbow lever havi'ngone arm. extending through a longitudinal slot in the body and into the slot in the said device and having-theother arm lying in the said longitudinal slot and extending toward the bottom ofthe body, yielding means for moving the rod' -upwardly and :holding the same an" lts upper P'OSllJIO-TI, and meanson the lever, adapted for engagement with the interior of- 'p'i-peffor retaining the "rod 'in itslower position, the said means includ ing a head on the lever arranged to enter a recess in the body when the rod is in its 7 lower position.

4. In an underreamer, a centrally bored body having a relatively large chamber at I its lower end, the upper portion of the chamber having lateralrecesses, bits in the chamber having portions at their upper ends projecting into the recesses and supporting the bits so that they may have free oscillating motion, arod reciprocable between the bits and in the'bore in the body, and a bitseparating head on the rod adapted to expand the bits in the chamber when the rod is moved upwardly and to allow them to collapse when at its lowest position, the relative cross-section ofthe-rod and bits being such as to allow the bits to swing toward each other at'their lower ends when the rod is lowered. and to prevent the upper ends of the bits moving toward each other so as to permit the bits to escape from the recesses. V

5. In an underreamer, a centrally bored body, bits connected to the lower portion thereof so asto have free oscillating motion, a reciprocable rod arranged between the bits and in the bore in the body, a bit separating head on the lower end of the rod arranged to separate bits when the rod isin its upperbody, having a lateral slot with a widened portion communicating with the central bore, bits supported by the lower end of the body, a rod reciprocable in the bore, a bit-separating head on the rod, a spring tending to move the rod upwardly, and an elbow lever having one end'lying lengthwise of the body and the other end extending through the lateral slot and urged upwardly by the rod,the last named end of the lever having a widened portion insertible through the widened portion of the slot,

whereby, when the widened portion of the lever enters the bore and moves lengthwise having a nut thereon, means preventing the thereof, the lever is retained in the lateral nut from turning, a bit-Wedging device on 10 slot. the rod non-rotatable With respect to the 7. In an underreamer, a centrally bored bits, and means preventing the bits rotating body having a chamber in its lower end, the in the body.

upper end of the chamber having a recess, Signed at Toledo, Ohio, this 20th day of bits suspended on the bottom Wall of the October, 1916. r

recess, a rod reoiprocable in the bore and CLYDE S. WRIGHT.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

